How much is professional indemnity insurance for architects?
Reviewed by Matthew Bartlett, Director, Apex Insurance Brokers Limited · Last reviewed 2026-08-05
If you run an architectural practice, PI insurance is not optional in spirit — it protects you against claims that your design, advice or specification caused a client financial loss. But when architects ask "how much will it cost?", the honest answer is that it depends on your specific practice. Below we explain the drivers that move the premium up or down, so you understand what you are actually paying for and how to keep the cost proportionate.
Why there is no single price
PI is underwritten individually. An insurer looks at your practice's risk profile and prices to it, rather than applying a flat rate. That is why comparison sites and rough "averages" are unreliable for architects: a sole practitioner doing domestic extensions and a multi-partner firm designing multi-storey residential blocks sit at completely different ends of the risk spectrum, even if both call themselves architects.
The RIBA Code of Professional Conduct and the ARB Architects Code both require architects to hold adequate and appropriate professional indemnity cover, so the question is rarely "should I buy it?" — it is "what will my particular practice cost to insure, and why?"
The main drivers of your premium
Underwriters weigh several factors together. Understanding them helps you see where your premium comes from — and where a broker can present your practice more favourably.
| Driver | Why it moves the premium |
|---|---|
| Fee income / turnover | The primary rating factor. Higher fee income means more work exposed to potential claims, so premiums scale with it. |
| Type of work | Domestic and small commercial work is generally viewed as lower risk than structural, high-rise, cladding, or complex mixed-use schemes. |
| Sector risk | Certain sectors carry heightened scrutiny — for example, work involving external wall systems or cladding — and can affect availability and pricing. |
| Limit of indemnity | A higher limit (£2m or £5m versus £1m) increases the premium, but may be contractually required by clients. |
| Claims history | Prior claims or circumstances notified to insurers raise the perceived risk. A clean record helps. |
| Excess chosen | A higher voluntary excess (the amount you pay per claim) usually reduces the premium, but increases your own exposure. |
| Risk management | Written contracts, appointment terms, QA processes and CPD signal a well-run practice and support a better rate. |
Choosing your limit of indemnity
The limit of indemnity is the maximum an insurer will pay for a claim (or in aggregate over the policy year). It is one of the biggest levers on cost, and choosing it well matters.
- £1m — often the entry point for smaller practices doing lower-value domestic work, where client contracts do not demand more.
- £2m — a common middle ground for growing practices and many commercial appointments.
- £5m — typical where larger developers, public-sector clients or contract terms require a higher limit.
Your limit is often dictated by your appointment documents rather than by choice. Many client contracts specify a minimum PI limit that must be maintained, so it pays to check your contracts before you buy. Setting the limit too low can leave you in breach of an appointment; setting it needlessly high inflates the premium.
Want a figure for your specific practice? Tell us your fee income, project types and required limit, and we will approach the market for you.
Get a PI quote →Why architects' PI is a specialist buy
Architects' PI is written on a "claims made" basis, meaning the policy that responds is the one in force when a claim is made — not when the work was done. That creates two features that affect long-term cost:
- Continuity matters. You need to keep cover in place year after year to stay protected for past projects. Gaps in cover can leave old work exposed.
- Run-off cover. When you retire, merge or close the practice, you may need run-off cover to protect against claims arising from historic work — an ongoing cost to plan for.
Because design liability can surface years after completion, insurers price architectural risk carefully. This is a market where wording and terms vary meaningfully between insurers, so the cheapest headline premium is not always the best value.
How a broker helps you control the cost
A specialist broker does more than fetch a price. We present your practice to insurers in the best light and make sure the cover actually fits how you work. Practically, that means:
- Approaching insurers who understand architectural risk, rather than relying on one quote.
- Framing your risk management — contracts, QA, project mix — so underwriters see a well-run practice.
- Matching the limit and excess to your client contracts and appetite for risk, avoiding both under-insurance and over-paying.
- Checking exclusions and conditions so a lower premium does not hide a gap that bites at claim time.
- Supporting you at renewal and if a claim or circumstance ever needs notifying.
The value is not just a number — it is a policy that responds when you need it, at a premium proportionate to your genuine risk. Start a quote with Apex and we will do the legwork across the market.
Common questions
Is PI insurance a legal requirement for architects?
There is no single statute setting a premium, but the ARB Architects Code and RIBA Code of Professional Conduct require architects to hold adequate and appropriate professional indemnity cover. Client appointments frequently specify a minimum limit too.
Will my premium fall if I have no claims?
A clean claims record generally supports a more favourable rate, because it lowers the risk an insurer perceives. It is one driver among several, though — fee income, work type and chosen limit still shape the final figure.
Why can't you just tell me a price?
Because architects' PI is individually underwritten. A meaningful figure needs your fee income, project types, required limit and claims history. Give us those details and we will return a quote built around your actual practice.
Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority (FRN 724952). This guide is general information, not advice on a specific policy or a substitute for your policy wording.